To serve the purpose for which it is intended a reservoir liner must prevent the passage of liquid from the pool it contains through the liner to the surface which is covered by the liner. A problem of seepage through the liner can develop when the lining material is not resistant to chemical action of the liquid that it contains. The solution of the problem is to use a material for the liner which is not subject to reaction with the liquid that is contained within the reservoir. In most cases, where the liquid being contained will separate into two layers, only one of which poses a problem of reaction with the liner material, using a nonreactive liner material for the entire reservoir is not economically feasible.
We have found a method for lining a liquid reservoir which eliminates the problem of reaction between the reservoir liner and a layer of liquid contained in the reservoir. The use of this liner is also economically feasible.
We have also discovered a method for securing sheets of liner material to each other so that leakage of the contained liquid through the liner at its seams is eliminated.
It is therefore an object of this invention to provide a more economical method for lining a liquid reservoir for containing layered liquids in which one of the liquid layers is reactive with the materials of construction usually used for reservoir liners. It is another object of this invention to provide an economical reservoir liner for use with layered liquids one layer of which will react with normally used liner materials. It is still another object of this invention to provide a method for uniting sheets of construction material used as reservoir liners to produce a nonleaking seam.
By the method of this invention a reservoir which contains a distinct layer of reactive liquid with a layer of nonreactive liquid is lined in the section of the reservoir which contains the reactive liquid with a liner material resistant to reaction with the reactive liquid and the remainder of the reservoir is lined with a liner material which is not resistant to reaction with the reactive liquid.
In one embodiment of the invention the materials of construction are thermoplastic film or nonwoven fabric which are precoated with liquid resistant material and the sheets of construction material are fixed together in an appropriate arrangement in the reservoir. In another embodiment of the invention porous nonwoven fabric is arranged to cover the reservoir and liquid resistant material is then applied to the appropriate portions of the backing after the backing is in place.
In still another embodiment of the invention sheets of lining material are fastened together in a liquid proof seam by facing the edges of two separate sheets, overlapping the sheet edges with a strip of nonwoven fabric which extends around the edge of the face sheets producing a laminate of four strata of sufficient width to be sewn, sewing through the four strata to unify them and coating the nonwoven fabric with a liquid resistant material.